Feeding solid reagents in pulverulent condition



8. G. CALL April 29, 1941.

FEEDING SOLID REAGENTS IN PULVERULENT CONDITION Filed July 1, 1939 2Sheets-Sheet 1 INVENTOR bny'dlm'n 4 fall 0 T? 1 2 ATTORNEY FEEDING SOLIDREAGENTS IN PULVERULENT CONDITION Filed July 1, 1939 2 Sheets-Sheet 2INVENTOR' flflyamz'lz 6 fall 9 7(708 ATTORNEY Patented Apr. 29, 1941UNITED STATES PATENT OFFICE.

FEEDING SOLID REAGENTS IN PULVERULENT CONDITION Benjamin G. Call,Tacoma, Wash, assignor to American smelting and Refining Company, NewYork, N. Y., a corporation of New Jersey Application July 1, 1939,Serial No.-282,387

4 Claims. (Cl. 302-52)- for this treatment is often received in a dampcondition and is practically always lumpy. Various difilculties areaccordingly involved in introducing the same into the bath in a uniformand controlled manner.

It is accordingly an object of the present invention to provide meansfor introducing the soda ash in the bath in a uniform manner regardlessof the condition in which the soda ash is received.

Another object is to provide an apparatus for the above purpose havingmeans for agitating or breaking up the lumpy material and feeding thesame into an injector in a condition suitable for being picked up by thecurrent of air or other gas and being delivered thereby to the desiredpoint.

Fig. 2 is a view of the same device taken at right angles to that shownin Fig. 1;

Fig. 3 is a view taken along the line 3--3 of Fig. 1 looking in thedirection of the arrows; and

Fig. 4 is a view taken along the line 4-4 of Fig. 3 looking in thedirection of the arrows.

Referring to the drawings. more in detail, the invention is shown asembodied in a device comprising a vertical cylindrical tank orreceptacle l having a conical top H having an opening l2 therein throughwhich the solid material is charged, said Opening being closed by asuitable cap i4.

The receptacle i0 is also shown as provided with a tapered conicalbottom l5 terminating in a discharge opening l6 surrounded by a bottomflange IT. A feeding chamber I8 is provided with a flange i9 which issecured to the flange l6 and forms a continuation of the conical bottom15. This feeding chamber may be provided with feeding of the reagent.

a cylindrical wall 20 in which a propeller 2|, to be described, isseated.

The propeller 2|, as shown more in detail in Figs. 3 and 4-, comprises ahub 23 and an outer rim 22 which is adapted to form a comparativelyclose fit within the wall 20 of the feeding chamber 18. A plurality ofblades v24 extend between the hub 23 and the rim 22. In the embodimentshown, these blades are of helical formation, with the leading edge 24aof each blade spaced from and overlapping the trailing edge 24b of thepreceding blade for the purpose to be set forth.

The hub 23 of the propeller 2i is secured to a vertical shaft 26 whichextends upwardly through the receptacle I0 and through a suitableopeningin a top plate 21 which is secured tothe conical top H of thereceptacle by suitable means, such as by bolts 28. Suitable bearingmeans for the shaft 26 are provided, such, for example, as a bearing 30carried by a bracket 3| which is secured to the top plate 21 by bolts32(Fig. 2).

Thrust bearings may be formed by a bearing ring 34 secured to the shaft26 beneath the bearing 30 and by a' bevelled gear 35 which is secured tothe top of the shaft 26 above said bearing 30. A packing gland 36 may beadjustably secured to the top plate 21 as by bolts 38 (Fig. l) forforming a tight seal around the shaft 26.

For driving the bevelled gear 35, a motor 40 is provided which issuitably mounted on a bracket ll secured to the top H of the receptacle.The motor 40 drives through a set of reduction gears, not shown, mountedwithin a housing 42 and driving'a bevelled pinion I3 meshing with thebevelled gear 35.

The feeding chamber i8 communicates at its bottom with an injector 45comprising an air nozzle 46 communicating with an air inlet pipe 41which is adapted to supply air under pressure thereto and containing acontrol valve 48. A pipe 49 communicates from the air pipe 41 to theinterior of the receptacle Ill so as to equalize the air' pressure andthus facilitate the proper The injector 45, the parts of which aresecured with a wing nut as shown in Fig. 2 to facilitate removal of theparts for cleaning, is adapted to pick up the powdered material receivedfrom feeding chamber i8 and to feed the same along with the currentofair (or other gas) through a duct 50 which communicates with a hose orthe like (not shown) for feeding the pulverized material to the bath fortreatment. The hose is, of course, suitably pro vided with a metal tipor pipe extending below the surface of the bath for introducing thereagent at the desired point therein. The entire device is supported onbrackets 5| and 52, brackets 5i carrying an axle'53 on which wheels 54are journalled. The bracket 52 carries a spindle 56 attached to a yoke51 carrying a wheel 58. A suitable handle 59 is pivotally connected, asat 60, to the yoke 51, thus serving to guide and steer the apparatuswhen same is moved from place to place.

In the operation of the above described apparatus, the material to befed, such, for example, as powdered soda ash which may be in a damp orlumpy condition, is charged into the receptacle in through the openingl2, after which the cap [4 is secured in place thus sealing theapparatus against egress of air or gas and the entrance of furthermoisture.

With the propeller 2| stationary, the overlapping blades 24 form asubstantially tight closure for the bottom of the receptacle and preventthe materialfrom falling therethrough. When it is desired to feed thematerial for use as a reagent, air under pressure is supplied throughthe pipe 41 to the injector 45 and to the interior of the receptacle viapipe 49. The motor 40 is caused to drive the propeller 2| in a directionsuch that the leading edges 24a of the blades 24 bite against andpulverize the material within the receptacle and feed the samedownwardly to the feeding chamber IS. The blades 24, in addition tobreaking up the lumps and suitably pulverizing the material, also serveto agitate the material and to maintain the same in proper feedingcondition. The material thus fed by the propeller 2| is picked up by theair current in the injector 45 and is fed along with the current of airthrough the duct 50 to the bath in the manner above outlined.

It may be noted that the rate of feed can be accurately controlled by.controlling the speed of operation of the propeller 2|. The propellerprovides a positive feed and prevents the flow of material into thefeeding chamber except in response to the feeding action of thepropeller itself. The maximum size of the particles which can be fed tothe chamber i8 is automatically determined by the spacing and speed ofrotation of the blades. The propeller accordingly serves to break up andfeed the material regardless of its previous physical condition. Thedevice is thus adapted to receive the material in whatever condition inwhich it may be supplied thereto and to feed the same in a uniform,pulverulent state without any pretreatment such as drying or breaking upof the lumps, etc.

While the device has been shown as portable, it can, of course, beconstructed as a stationary, permanent unit of'the furnace equipment.Furthermore, it is to be understood that the device is capable ofvarious uses, as will be readily apparent to a person skilled in theart, the particular use set forth being a typical one and illustrativeof its various adaptations.

Certain specific terms and disclosures have been used herein forconvenience in referring to various details of the invention and fordescribing same. Naturally, various changes and modifications may bemade within the scope of th invention as defined by the appended claims.

What is claimed is:

1. Apparatus for feeding a solid, pulverize material comprising areceptacle for said material having a discharge opening, a rotatablymounted propeller comprising a rim seated in .said discharge opening,the blades of the propeller forming, when stationary, a substantiallycomplete closure therefor, a vertical shaft driving said propeller, adriving motor carried by said receptacle, mechanical driving meansinterconnecting said motor and said shaft whereby said propeller isdriven at a speed determined by the speed of operation of said motor, afeeding chamber mounted to receive material fed through said dischargeopening by said propeller, and a gas injector means associated with saidfeeding chamber for picking up said material and feeding the same.

2. Apparatus for feeding a solid reagent in pulverulent form comprisinga receptacle for said material having a discharge opening, a rotatablymounted propeller comprising a rim seated in said discharge opening,said propeller having a plurality of helical blades with their endsoverlapping so as to form a closure for said discharge opening when saidpropeller is stationary, a vertical shaft driving said propeller in adirection to cause same to agitate, pulverize and feed the materialthrough said discharge opening, a driving motor carried by saidreceptacle, mechanical driving means inter-connecting said motor andsaid shaft whereby said propeller is driven at a speed determined by thespeed of operation of said motor, a feeding chamber carried by saidreceptacle below said propeller, and air injector means connected toreceive the material thus fed by said propeller and to feed the same.

3. Apparatus for feeding a solid reagent comprising a receptacle forsaid material having a discharge opening, a rotatably mounted propellercomprising a rim seated in said discharge opening, said propeller havinga plurality of helical blades with their ends overlapping so as to" forma closure for said discharge opening when said propeller is stationary,a vertical shaft driving said propeller in a direction to cause the sameto agitate, pulverize and feed the material through said dischargeopening, a driving motor carried by said receptacle,'mechanical drivingmeans inter-connecting said motor and said shaft whereby said propelleris driven at a speed determined by the speed of operation of said motor,a feeding chamber carried by said receptacle below said propeller, airinjector means adapted to pick up and feed. material supplied to saidfeeding chamber by the operation of said propeller, and means equalizingthe air pressure in said air injector means and within said receptacleto facilitate the feeding of reagent therefrom.

4. Apparatus for feeding a solid, pulverized material comprising areceptacle having a tapered bottom terminating in a discharge opening, apropeller comprising a rim seated in said discharge opening and bladesforming, when stationary, a substantially complete closure for saidopening, a vertical shaft driving said propeller, said shaft extendingupwardly through the top of said receptacle, bearing means for saidshaft comprising a bracket mounted on said top, a packing gland forminga seal with said shaft, a driving motor carried by said receptacle,mechanical driving means inter-connecting said motor and said shaftwhereby said propeller is driven at a speed determined by the speed ofoperation of said motor, a feeding chamber carried by said receptaclebelow said propeller, and air injector means adapted to pick up and feedthe pulverized material supplied to said feeding chamber by theoperation of said propeller.

BENJAMIN G. CALL.

